Does anyone come in to buy a plain bag of potato chips? "Rarely," Bawazir said.

If Flamin' Hot Cheetos have any serious competition for young urban allegiance, it's from a Mexican import called Takis, made by Barcel. Especially popular in the Latino community, Takis are tortilla chips that are rolled, fried and coated in lime and chili powder.

"The first time I ate Takis, I thought I would just eat a couple and put it away, but I ate half the bag," said Iman Rana, a senior at Whitney Young High School in Chicago. "They are just like a better version of everything."

While some kids take sides, others swear by both. In August the bright red rivals were jointly exalted in an irresistible music video called "Hot Cheetos and Takis" that has scored more than 3 million views. Created as part of a YMCA-sponsored writing workshop, the song features a group of pint-size urban rappers from Minneapolis reciting the hooky refrain:

"Hot Cheetos and Takis/ Hot Cheetos and Takis/ I can't get enough of these Hot Cheetos and Takis/ Got my fingers stained red and I cannot get them off me/ You can catch me and my crew eating Hot Cheetos and Takis."

Rockford Public Schools used to sell about 150,000 bags of Flamin' Hots each year, often topped with hot nacho cheese. Students complained about the 2010 ban but "have learned to adjust," said the district's director of nutrition services, Renita Weiskircher. The district still sells baked regular Cheetos — with cheese sauce on the side.

At Niles West High School in Skokie, "junk food" sales are banned, so Flamin' Hot sightings are a cause for excitement.

"It means someone brought Flamin' Hots from home or the store," said senior Morgan Gstalter. "They are rare, so you become the coolest kid in class if you have them that day."

In Chicago Public Schools, students report that Flamin' Hots are everywhere. Baked versions are sold in some district vending machines, and regular bags can be sold as school fundraisers.

"Eight out of 10 kids bring them to school," said Lake View senior Abigail Hernandez. "And I used to be one of them in middle school. I ate them every day, even for breakfast, and I got really big. There were days when, if my mother didn't buy them for me, I would get so mad. … It took me three months to quit."

Are snacks like Flamin' Hots addictive? For some people, maybe so. Gene-Jack Wang, a senior scientist at Brookhaven National Laboratory in New York state, in September co-wrote a review of the neurobiological overlaps between obesity and substance addiction.

In both conditions, the paper notes, the perceived importance of the reward (food or drugs) becomes exaggerated at the expense of other rewards, triggering "abrupt dopamine increases" that "can override the brain's … control mechanisms" that would normally moderate consumption.

"You can almost equate the craving (for processed food) to that of cocaine," said Wang, a radiologist.

Gearhardt said she is troubled by research suggesting that traditional whole foods might lose their appeal after taste buds become accustomed to certain processed foods.

"In addition to the taste-bud shift, there is some suggestion that these foods could alter the brain's dopamine (reward) system," she said, "and we may no longer be as sensitive to the foods that used to be rewarding."

She said one study found that rats that ate "junk food" and were put back on a regular diet would "walk through electrified mazes, shocking their little feet in search of the junk food again."

But should food-makers be punished for doing their job — essentially making something taste so delicious that customers can't get enough?

"I don't blame them for creating it," Gearhardt said. "I think there is a lot of competition to create … the most rewarding and potentially addictive product possible so people crave it and they want to buy another bag.

"But once the evidence has come out that they have created a substance that is capable of hijacking the neural system ... then I feel like it falls under their ethical obligation to ask how this should affect the way they market and push the product."

Angela Odoms-Young, who studies dietary patterns in urban communities, said she appreciates the emerging work on food addiction but asks: "Do we really need to prove that people are addicted to something before we start limiting things we know are unhealthy to our children, things that have been linked to poor health outcomes for decades?"

"We know that Flamin' Hot Cheetos are, at best, a 'sometimes food,'" said Odoms-Young, an assistant professor in kinesiology and nutrition at the University of Illinois at Chicago. "But you have some kids eating three or four bags a day, and that is inevitably going to replace healthier foods."

Some parents may not realize how often their children are eating Flamin' Hots until they wind up taking the kids to the doctor over "concern for blood in their stool," according to Dr. Kathleen Berchelmann, a pediatrician at St. Louis Children's Hospital.

Though parents may have a scare over the false alarm — caused by red food dye — Berchelmann said it also offers a great opportunity for a lesson on gluttony and moderation.

"When you eat something that sends you to the ER with your parents," she said, "that's not something you forget."